The purpose is to investigate whether HIV and HIV medication can affect certain areas of brain function. This study will look at possible changes in brain function including memory, concentration and thought processes to see if there are any differences between the two doses of efavirenz used in the Encore1 study and also the level of efavirenz in the blood

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study.
To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01516060